1. Field of the Invention
This invention relates to a rear independent wheel suspension system of the type having wheel arms and torsion bars.
2. Background of the Invention
Suspension systems of this general type are already known. For example, such a suspension system is described in French Pat. No. 80.15 444, filed by Regie Nationale des Usines Renault. Such suspension systems have an L-shaped housing joining corresponding ends of the wheel arms to the stub axles. The L-shaped housing is located approximately beneath the steering knuckle spindles. Two torsion bars are housed in the L-shaped housing. The torsion are joined in their middles by a connecting shackle. The free ends of the torsion bars are joined to the body of the vehicle and to the wheel arms, respectively.
This type of suspension system, while it is particularly advantageous with respect to its weight, is not entirely satisfactory in certain situations. For instance, when a front wheel drive vehicle having such a suspension system is in a sloping situation, the outside wheel in the turn undergoes a variation toward the opening, giving to the axle unit rather unfavorable oversteered characteristics.
Also, the length and the position of the legs of the L-shape housing, such as is described in the above patent, do not optimize the rigidity of gripping and of opening of the axle due to a skidding force. This can be reflected in a behavior deficiency with respect to supporting and longitudinal guiding of the vehicle when turning and therefore of keeping on course.